Multiple pipe unit adaptable to the drilling and pumping arts



Sept, 13, 1932. F. H. DAVIS ET AL.

MULTIPLE PIPE UNIT ADAPTABLE TO THE DRILLING AND PUMPING ARTS Filed Jan. 27. 1931 INVENTOR.

BY 2M 'i .5

Patented Sept. 13, 1 932 PA'TENT" OFFICE Farmers H. DAVIS AND FRANK F. DAVIS, 01-? MONTEREY, CALIFORNIA MULTIPLE rrrn UNIT ADAP,

TABLE TO THE DRILLING AND PUMPING ARTS Application :filedfianuary 27, 1931. Serial No. 511,616.

depths are attempted. 1 7 In respect to the drilling problem, great advantage would be gained if a drill bit either percussive or rotary "could be operated by motor disposed down the borehole, closeto the'w'ork, instead of by rotating a drill bit by meansof a string of drill rod revolved at the surface with all its attendant friction againstthewall of the holeandrwear of parts; or by applying walking-beam action to reciprocate the weight of a churn drill and its mile or so of cable.

In respect to the pumping problem involved, itis most desirable toplace a serles of pumps down a well, so as to pump by stages, each pump being provided with-its own motive power adajcent thereto, whereby each 'pump raises its own column of pumped fluid a certain height andthen transfers it to the next pump above, thereby distributing the load instead of attempting to handle the fluid in a single column. 7 j I Ineithercase, no matter whether drilling or pumping by sub-active means it is necessary to provide aplurality of pipes extending down the bore hole 'or well to convey different fluid matter up and down the hole; such as oil, or gas from the productivemeasures, and motive agent such as compressed air, electric power or steam from thesurface tov the sub-active motive means for running said pumps or drills. v

It should be noted that such strings of pipe quite frequently, an arduous task which up to the present has militated against the use of problemswhich increaserapidly as greater.

means such as an air engineer an electric have to be handled into or out of the holes each internal tube will be separate and convention multiple strings of pipe have been used for conveying fluid in boreholes and wells, but in all cases the different individual pipes have had to be screwed together separately and provided with individual packing means which had to be applied and removed at each coupling-together of the diflerent pipe pecltions when'putting in or pulling out of 10 e. i I

The primary object of our invention there fore, is to provide multiple-pipe units, each unit handlable as one individual length of pipe and provided with screw threaded means for coupling a series of such pipes together end to end. v a

' A unit of pipe in accordance with our invention comprises, an outer elongated, tubular casing or body, having closure members at each end thereof provided with screwthreaded elements for connecting a series of such pipes together for drilling or pumping purposes. Said closure members being axially and co-incidentally perforated to receive one or more-tubes passing longitudinally through said casing; the respective tube ends being rolled as boiler flues are rolled, and beaded, welded or otherwise secured to the respective closures so as to withstand heavyinternal and external pressures. v

A unit constructed in the above manner not'o'nly provides multiple fluid conduits, but affords a re-enforced structure of great torsional and tensional strength which is of great. importance in the art where such excessively long strings of drill-pipe have to transmit power, sustain their own weight and are occasionally subjected to heavy strains,

as when stuck in the hole. The coupling means are preferably of the tool-joint type familiar to the art, and provide -a shouldered portion adjacent the upper end of each unit whereby aunit or string of units may be suspended by the well known elevator means which co-acts against the under side of the shoulder.

A further object is to provlde a plurality of tubes within a tubular unit and so arranged that when a series of such units are coupled together to, forma string of pipe pass from the casing of one tinuous throughout the entire series or string.

Another object of our invention is to pro vide means to prevent the circumferential creep of the coupling joints, due to wear of the contacting closure surfaces, shutting off fluid communication between related tubes of contiguous units; and at the same time preventing escape of fluid from any individual tube to a non-related tube.

An important object is to provide an outer casing for each unit which may be used as-a conduit and also as means to drive a rotary drill bit; said casing being to co-operate with the conical wedge elements in familiar use with drilling apparatus for the supportof strings of pipe when being handled in or out of the hole.

A further object of the invention is to provide means for fluid communication extending through said joints whereby fluid may unit to the casing of adjacent units; and means whereby fi-uid'fiowis established through the various tool oints from the relative tubes of one unit to the companion tubes ofthe adjoining units. These objects are attained by the PGCUllZlP arrangement, construction andrelative combination of parts comprehended on our invention, set forth in the specification, pointed out in the claims and illustrated in the accompanying drawing forming a part thereof, in which Figure 1 shows an elevation of a string of pipe illustrating our invention in relation to a borehole.

Figure 2 shows an elevational mid-sectional view of the invention.

Figure 3 shows a top plan View of the female coupling.

Figure 4 shows a vertical section taken on the line IVIV of Figure 7.

Figure 5 shows a section taken on the line V'V of Figure 2.

Figure 6 shows a bottom plan view of the male coupling B.

Figure 7 shows a top plan view of a female coupling arranged for a different number of internal tubes or condults.

Figure 8 shows a bottom plan View of the male couplin arranged to cooperate with the female coupling shown in Figure 7.

Figure 9 is a cross section through a multiple-pipe of the present invention showing a secondary construction.

Similar indicia of reference refer to similar parts throughout the several views In carrying out our invention we provide a tubular body or casing C having the coupling elements A and B secured to the respective upper and lower ends thereof. Obviously, various other forms of couplings could be employed without departing from the spirit of the invention; but,-for the purpose of this specification, we prefer to illustrate couplings presenting the general outward a-p-i further adapted pearance of the tool-joints known to the art.

Referring to the drawing it will be noted that the coupling element A comprises the body 1, the face 2, the internally-threaded recess 3, the closure portion 4, the screwthreaded plug portion 5, the shoulder 6 and the contact table 7.

The coupling element B comprises the body 8, the externally-threaded pin 9, the closure portionil'Qathe pinshoulderll', thelpin con tact table 12, the plug portion 13, and the shoulder 14.

In order to have a clear understanding of the invention it should be stated that in the process of-manufacture, the blanks for the elements A and B are first machined to screw together as shown in Figure 4, with the respective planes of the tables 7 and 12 in precise contact with each other, but leaving a slight space 15 between the face 2and the shoulder 11, thereby affording a positive leak-proof contactbetween the respective contact tables. The respective plug portions 5 and 13 are screwthreaded tointerengage complement means at the respective ends of the casing C. The casingC is of any suitable length that can be transported by ordinary means or handled in a derrick, the longer the better as requiring fewer coupling elements.

A couplingelement A. and a coupling element- B are provided'for each casing C, the respective parts being very. solidly drawn together with the. respective ends of said cas ing abutting firmly against the adjacent shoulders 6 and 14. For additionalstrength, and to guard against circumferential movement of any component part with relation to the others, said abutting parts may be welded together, thereby affording additional tensional and'torsional strength tothe unit.

Assuming that a multitubular unit as represented by Figures 2, 3, 5 and 6 is to be constructed, and that the partly finished coupling elements Aand B are. connected with a casing C as abovedescribed, it will be noted that said casing with its respective closures 4 and 10 imperforated constitutes a hermetically sealed, tubular unit arranged to be interchangeably attached to others of its kind.

Aiconcentricseries of holes as 16, and the central hole 17, are now drilled axially perforating the closure portion 4 of the element A; holes as 18, and the central hole 19, are now. drilled axially perforating, the, closure portion 10 of the element B, all the holes 18 being in vertical alinement with the holes 16. The embouchures of all saidholes are preferably enlarged with a broach tapering inwardly of'sa'id casing;

The tubesn20. and the tube 21- are'now assembled in the casing G through the respec tive holes, being anicer fittherefor and cut the proper length tovform. a-zfiush joint after LED being expanded, welded or otherwise secured individually to the contacting structure of the respective closure portions 4.- and 10.

It should be noted that the holes 22 are drilled to axially perforate the element B, the holes 23 are provided to communicate therewith, the latter being slotted to guard against fluid being shut ofi by circumferential creep of said coupling elements. a

It will be further noted that recesses as 24: are provided in the table 7 one leading to each tube 20. Said recesses being preferably arcuate and struck with the same radius that cuts the center of said. tubes 20. As the object of said recesses is to maintain open communication between the tubes of one unit with the related tubes of contiguous units we arrange the machining of the coupling elements A and B so that, when first in use, fluid flowing from "the tubes 20 "of one unit will follow the recesses as in an offset conduit which gradually shortens as the related tables wear and abut against each other at different points approaching vertical alinement of the tubes 20 of contiguous units.

Constructed as above described the multitubular unit of our invention comprehends siX individual conduits; namely, the four tubes 20, the tube 21 andthe space which comprises the space within the casing C surrounding said respective tubes.

Figures 4, 7 and 8 illustrate a multitubular unit comprehending five conduits, comprising three tubes 20, the central tube 21 and the casing interior 25.

The Figures 2, 3, 5 and 6 contrasted with the Figures l, 7 and 8 are not intended to represent primary and secondary construction, but are given to show the adaptability of our invention as being capable of using a fewer number of tubes in boreholes of less diameter. Figure 9. however shows a multitubular unit of secondary form comprising the central conduit which corresponds to the tube21 and the cellular conduits 26 set off from each other by the webs 27 disposed radially in the annular space between the exterior of the tube 21 and the interior of the casing C, said webs obviously extend throughout the length of the unit and are adapted to cooperate with the respective coupling elements A and B to provide means to convey a plurality of individual fluid substances throughout a string of similar units. I

In Figure 1 we show an elevational view of coupled multitubular units of our invention in relation to a borehole 28 provided with a conventional rotary apparatus 29, having the wedge slips 30 and the elevator 31 coactable against the shoulder 6 of the coupling elements A. As so coupled fluid can pass from unit to unit through the individually related tubes and fluid passage is assured from the spaces 25 of one unit to another 65 through the respective holes 22 and 23.

It is believed that the construction, operasince in actual practice they attain the features of advantage set forth as being desirable in the statement of the invention and the above description.

Numerous changes in the details of construction, and in the combination and arrangement of parts may be resorted to without departing from the spirit or scope of the invention as hereinafter claimed or sacrificing any of its advantages.

1. As a new unitary article of manufacture, a multitubular pipe comprising an outer casing, a plurality of longitudinal internal tubes traversing the casing and rigidly mounted therein, a coupling element at each end of the casin having an outwardly disposed contact table and external shoulders on the coupling elements outwardly of the,

contact tables normally spaced when the tables are contacting to permit further adjustment of the elements. to compensate for wear.

2 As a new'unitary article of manufacture, a multitubular pipe comprising an outer casing, a plurality of longitudinal internal tubes traversing the casing and rigidly mounted therein, a coupling element at each end of the casing having an outwardly disposed contact table and external shoulders on the coupling elements outwardly of the contact tables normally spaced when the tables are contacting to permit further adjustment of the elements to compensate for wear.

each coupling having a closed wall provided with bores into which the ends of the tubes are set.

3. As a new unitary article of manufacture, a multitubular pipe comprising an outer casing, a plurality of longitudinal internal tubes traversing the casing and rigidly mounted therein, a coupling element at each end of the casing having an outwardly disposed contact table and external shoulders on the coupling elements outwardly of the contact tables normally spaced when the tables are contacting to permit further adjust- .ment of the elements to compensate for wear,

each coupling having a closed wall provided. with bores intowhich the ends of the tubes are set, and one of said couplings having an arcuate groove extending from each bore to assure registration of the tubes of adjacent casings.

In testimony whereof we affix our signatures this 19 day of January 1931.

FRANCIS H. DAVIS.

FRANK F. DAVIS. 

